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The crystalline morphology of some FEP copolymers, prepared by different methods, with different hexafluoropropylene (F_6) contents was studied by means of small angle light scattering technique.The results obtained show that the main factors which affect the crystalline morphology are the content of F_6 and the conditions for crystallization. The morphological structure of these copolymers could change from rod-like to spherulitical, as the F_6 content changed from 2% to 14—19% under usual air-quenching condition. However, rod-like crystalline structure would form under very low rate of cooling (0.2℃/min). Some H_v patterns show that fine structure also exists in addition to the two—and three-dimensional spherulites coexisting in the specimens prepared under certain crystallization conditions.
The crystalline morphology of some FEP copolymers, prepared by different methods, with different hexafluoropropylene (F_6) contents was studied by means of small angle light scattering technique. The results obtained show that the main factors which affect the crystalline morphology are the content of F_6 and the morphological structure of these copolymers could change from rod-like to spherulitical, as the F_6 content changed from 2% to 14-19% under usual air-quenching condition. However, rod-like crystalline structure would form under very low rate of cooling (0.2 ° C / min). Some H_v patterns show that fine structure also exists in addition to the two-and three-dimensional spherulites coexisting in the specimens prepared under certain crystallization conditions.